Association of glycation markers with the progression of the initial stages of diabetic non-proliferative retinopathy in type 2 diabetes mellitus

Relevance. In the development and progression of non-proliferative diabetic retinopathy (NPDR) in type 2 diabetes mellitus (DM2), an important role belongs to the activity of the protein glycation process and the formation of advanced glycation end products (AGE).Objective: To link glycation markers carboxymethyl lysine (AGE-CML) and circulating AGE receptor (sRAGE) to the progression of early-stage of nonproliferative diabetic retinopathy in patients with type 2 diabetes.Material and methods. 91 patients (182 eyes) with diabetes mellitus aged 42 to 80 years were examined. The control group included 25 people of the appropriate age. At the time of the initial examination and 1 year later, the NPDR stage was established according to the modified ETDRS system of clinical signs Airlie House. The content of glycation markers was determined by enzyme-linked immunosorbent assay in blood plasma. MedStat and MedCalc v.15.1 (MedCalc Software bvba) software packages were used for statistical research.Results. The initial manifestations of diabetic retinal lesions occurred in 27.5% of patients, began after 7.16 ± 1.11 years and were accompanied by higher glycemia. The content of AGE-CML in diabetes mellitus was significantly increased compared to the control, which was more pronounced in the presence of initial retinal changes - was 1.3 times higher than in patients without such changes (p = 0.015). The content of sRAGE decreased several times, which was also associated with the presence of diabetic retinal changes - in their presence it was 2.2 times lower (p <0.001). The content of AGE-CML was significantly higher (1.5 times; p <0.001) in the presence of NPDR progression during 1 year of observation than without it. The content of sRAGE in the presence of progression was 1.6 times (p <0.001) lower. Conclusion. Thus, accumulation of blood AGE-CML and sRAGE reduction is connected with the occurrence and progression of NPDR.Key words: nonproliferative diabetic retinopathy, type 2 diabetes mellitus, Advanced Glicated End Products, AGE-CML, sRAGE